1 Definition of inputs and ways to compute the outputs - Theory » History » Version 4

JANVIER, Thibault, 12/15/2015 10:46 AM

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h3. 1. Definition of inputs and ways to compute the outputs - Theory
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+1. Display of the power spectrum+
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p=. !Signal_to_power_spectrum.png!
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+Figure 9: Computation of the Power Spectrum+
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The incoming signal passes through the "power spectrum block" of LabView. The power spectrum of the given signal is then displayed.
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+2. Computation of the power+
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p=. !Power_Spectrum_to power.png!
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+Figure 10: Computation of the Power+
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The value of the autocorrelation of the signal taken at 0 gives the total power of the signal. If the signal is noisy, the result will be the power of the useful signal added to the one of the noise.
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+3. Display of the constellation+
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Now, let’s have a look to digital results. We want to observe the constellation of the signal and some results like mean error vector magnitude or mean phase error. Our signal analyser does not determine automatically what is the constellation used to transmit the signal, we have to know it before and to enter it in the program as a parameter. Then we can observe the received constellation, the mean error vector magnitude, the mean phase error, and the mean magnitude error. 
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!evm.gif!
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+Figure 1: Measures explanation scheme+